Caption: Yellow fever virus particles. Transmission electron micrograph (TEM) of yellow fever virus particles (virions, yellow). Yellow fever is endemic in tropical Africa and South America. It is transmitted to humans by infected female Aedes aegypti mosquitoes and can cause fever, nausea, headaches and yellowing of the skin due to jaundice. In serious cases there may be liver and kidney damage. There is no treatment for yellow fever and 5% of those infected die. However, vaccination can provide immunity.